Forex trading is an extremely lucrative, but extremely risky, venture. If you make the right choices, or even just get lucky, you can very quickly become extremely rich. However, this is extremely unlikely and difficult to do.
There is only a certain amount of money available for people to have, so a trader in currency can only gain as much as another trader has lost. Add in brokers fees, and this becomes a negative-sum game. What that means is, everybody loses if they stay in long enough - some people are smart enough to stop while their ahead, and the others end up going broke.
This means it is incredibly important that you get out when you're ahead, instead of just throwing good money after bad. The leverage offered by brokers, sometimes as much as 200:1, is so large that even a small loss can completely wipe you out.
The most important thing to be aware of, and the mistake that the most people make, is not being prepared enough when they start trading. You might not know anything about forex, or maybe you've read a book or two, or even taken a course, but nothing can really prepare you for the experience itself.
Perhaps you've even tried paper trading, and you think this will let you learn what you need to know. However, no matter how good you are at paper trading, it's still just a game. No amount of training in fake trading can help you when it comes to the real thing.
The price of learning by experience is extremely high, because of the huge amount of money involved, which enlarge any mistakes. At the start of your career, you need some expert guidance to have a chance of success, and for that the best you can get is an experienced mentor. Failing that, there are computer programs available now that can do almost as well. Granted, they can't talk to you face to face or give you advice about anything besides trading, but if your just starting out a good system can dramatically increase your chances of success. Forex trading involves huge amounts of money, and anything that gives you a better chance of holding onto that money, or even increasing it, is a must-have for a new investor. Or even for an old one, in fact, as a second opinion can be a big help.
There is a lot you can read about in books - heck, you're reading some of it here. But these words are only the tip of the iceberg, and there is no way to convey, in an impersonal book or article, what the best thing is for you to do. So if you want to do well with forex trading, then you need a good system to work with, and someone who can offer you good advice when you need it.